docs: def _focus_instance(self):
          """ In instances, the ``focus()`` classmethod is replaced with this instance method. """
          if self._title:
              Debug.log(3, "Focusing app with title like ({})".format(self._title))
              PlatformManager.focusWindow(PlatformManager.getWindowByTitle(re.escape(self._title)))
              if self.getPID() == -1:
                  self.open()
          elif self._pid and self._pid != -1:
              Debug.log(3, "Focusing app with pid ({})".format(self._pid))
              PlatformManager.focusWindow(PlatformManager.getWindowByPID(self._pid))
          return self